Electronic Journal of Plant Breeding

**Study on gene action of yield and its attributes in rice (Oryza sativa L.) under phosphorus-deficient conditions using Griffing’s approach**

Fri, 04 Jul 2025 05:24:06 +0000

Phosphorus (P) deficiency drastically limits rice production in tropical soils, necessitating the development of P-efficient varieties. The present study evaluated the combining ability of eight rice parents and their 28 F₁ hybrids, which were produced from a half-diallel cross, at the UBKV Research Farm in West Bengal during Kharif 2021–2023 under deficient P soil condition. The experiment was laid out in a randomized block design with three replications and genotypes evaluated for 14 yield related traits. Combining ability was analyzed using Griffing’s Method II, Model I, to estimate general (GCA) and specific (SCA) combining ability effects. Significant genetic variation was observed, with GCA exceeding SCA for traits like plant height and grains per panicle, indicating strong additive effects, while SCA dominated for P uptake and yield, suggesting non-additive contributions. Parents like MTU 7029 and Ranjit appeared as superior combiners, while crosses such as CR Sugandh Dhan 909 × BBII and Paolum Sali × Ranjit exhibited high hybrid vigor. Dominance variance surpassed additive variance across traits, favoring hybrid breeding strategies. These findings indicate prospective parents and crosses that can improve rice production and P-use efficiency in low-P soils, especially in the Terai Zone of West Bengal.

Keywords: Rice, combining ability, diallel, phosphorus, GCA, SCA

**Determination of breeding approaches for improvement of economic traits in Indian muskmelon (Cucumis melo L.) through assessment of gene action**

Fri, 04 Jul 2025 05:24:38 +0000

Muskmelon is an important cucurbitaceous vegetable due to its excellent taste, flavour, aroma and other quality traits present in its fruit. Architectural phenotypes of this crop have great potential to increase its fruit yield at the commercial level. Generation mean analysis was conducted in the year 2023 comprising five crosses of muskmelon (PMM-4A x Hara Madhu, PMM-4A x PMM-37, PMM-1 x Hara Madhu, PMM-32 x PMM-16, PMM-13 x PMM-16) derived from seven inbreds to study the gene action for implying correct breeding method to improve some important yield attributing traits. The results found in the present experiment suggest choosing specific breeding technique for a particular cross for improvement in a single character as both the type and intensity of gene action varied for a solitary trait in different crosses. Character-cross combination specified the role of simple additive gene for governing days to first female flower (Cross I and II) and total soluble solid content (Cross I, II, III and IV). Thus, simple pedigree method and selection in early generation could be adopted to improve these traits. Effect of dominance was observed in vine length (Cross-III) and number of fruits (Cross-II) where heterosis could be viable. Most of the cross combinations showed non allelic interaction in digenic level where duplicate epistasis was reported for all the traits like days to female flower (Cross III and IV), vine length (Cross I, II, IV and V), number of fruits per plant (Cross I and III), average fruit weight (Cross I,III, IV and V), fruit flesh thickness (Cross I, III,IV and V), fruit yield (Cross II and V) and TSS content (Cross V) indicating selection to be done in later generations at high intensity. Breeding methods like population improvement through biparental mating or recurrent selection would be effective to achieve sufficient improvement in these characters. On the contrary, the presence of complementary gene action in cross V for earliness, cross IV for number of fruits and cross II for fruit weight showed the significance of heterotic improvement.

Keyword: Gene action, Generation Mean Analysis, Muskmelon, Scaling test, Epistasis

**Molecular and phenotypic evaluation of restorer lines for bacterial blight and blast resistance for developing heterotic hybrids in rice (Oryza sativa L.)**

Fri, 04 Jul 2025 05:24:51 +0000

The present study was carried out with an objective to identify restorer lines harbouring fertility restoration genes and resistance to the biotic stresses, Bacterial Blight (BB) and blast diseases. Seventy-one breeding lines were screened for the presence of fertility restorer genes viz., Rf4 and Rf3 along with target disease resistance genes, Pi54 for blast and Xa21, xa13 and xa5 for BB. Phenotypic evaluation against BB and blast diseases was done by artificial inoculation and raising the plants in disease screening nursery. Simultaneously, selected parental lines along with previously identified R lines were crossed with two CMS lines viz., APMS6A and CRMS32A for developing experimental 176 F₁ rice hybrids. The rice hybrids along with seven checks were evaluated in Augmented RCBD for 15 yield and yield contributing traits. Based on the results of pollen/spikelet fertility analyses of the F₁ hybrids, parental lines were identified as restorers, partial restorers or partial maintainers. The identified highly heterotic rice hybrids will be subjected to large scale multi-location testing. The potential restorers identified in this study will be highly useful for three-line hybrid rice breeding for developing biotic stress-resistant rice hybrids with higher grain yield.

Keywords: Hybrid Rice, Bacterial leaf blight, Blast, Fertility Restoration, Heterosis,

**Multi-environment evaluation of combining ability and heterosis for root yield and attributing traits in ashwagandha [Withania somnifera (L.) Dunal]**

Preeti Basser, Hemlata Sharma, Amit Daheech, Ruchi Bishnoi and, Puneet Basser — Fri, 04 Jul 2025 05:25:05 +0000

Ashwagandha (Withania somnifera), a vital medicinal crop, suffers from limited genetic diversity, which constrains its yield potential on a commercial scale. Exploiting combining ability and heterosis can serve as effective breeding strategies to enhance productivity and alkaloid content. A comprehensive study was conducted during Rabi 2022-2023, involving 60 hybrids, their parental lines and standard checks (JA-20, JA-134 and RVA-100), evaluated in a randomized block design across three diverse environments. Significant variability was observed for alkaloid content, dry root yield and its contributing traits. To refine parent selection, combining ability analysis was performed, revealing that both general combining ability (GCA) and specific combining ability (SCA) were significantly influenced by environmental interactions. Parents, including UWS-23, UWS-60, UWS-13, UWS-79, UWS-100, UWS-104, UWS-131, UWS-134, GP-49 and GP-51, exhibited significant positive general combining ability (GCA) effects for dry root yield, indicating the predominance of additive gene action. Among these, UWS-100 emerged as a promising general combiner for both dry root yield and total alkaloid content. Furthermore, specific cross combinations such as UWS-104 × UWS-60, UWS-132 × UWS-10, and UWS-92 × UWS-10 demonstrated high standard heterosis for dry root yield over the superior check variety JA-20 in environment E₃. These hybrids also showed significant positive specific combining ability (SCA) effects, highlighting the role of non-additive gene action in trait expression. These findings highlight the potential of identified genotypes for use in hybrid breeding programs aimed 5at improving both yield and phytochemical composition in Ashwagandha. The integration of heterosis exploitation with combining ability analysis provides a strategic approach for developing superior Ashwagandha cultivars, offering significant scope for commercial cultivation and enhanced utility in the medicinal plant industry.

Keywords: Ashwagandha; Alkaloid content; Dry root yield; GCA; SCA; heterosis

**Stability analysis in rice (Oryza sativa L.) through AMMI and GGE biplots**

Fri, 04 Jul 2025 05:25:21 +0000

Rice (Oryza sativa L.) is a major staple known for fulfilling our dietary requirements. Continuous breeding efforts for widening its genetic base are essential to develop climate-resilient varieties in the future. In view of this, a stability analysis among 81 genotypes comprising of traditional landraces and released varieties was done to evaluate their yield-attributing traits across three seasons namely, Kharif 2022, Rabi 2023, and Kharif 2024. The AMMI and GGE biplot exhibited seven genotypes viz., KRG 45 (Sithiraikar), KRG 33 (Kulipadichan), KRG 21 (JGL), KRG 40 (Norungan), KRG 46 (Sivapu Kavuni), KRG 2 (Aanaikomban) and KRG 12 (CO 51) as the stable genotypes with high yield across seasons. Considering the per se performance for yield, KRG 2 and KRG 46 had the highest yield across seasons than the two checks viz., CO 51 and CO 55. Among the three seasons, Kharif 2022 was found to be ideal and exhibited a favorable influence on the genotypes for yield. Since, the three seasons were found to interact independently on the genotypes, they could be used to evaluate the upcoming breeding trials for testing stability in rice. The identified stable genotypes from this study could be advanced for further evaluation to develop climate-resilient rice varieties in future.

Keywords: Rice landraces, AMMI, GGE biplot, yield attributing traits

**Emergence of a new Xanthomonas oryzae pv. oryzae (Xoo) pathotype breaking the earlier resistance gene combination of improved Sambha Mahsuri**

Fri, 04 Jul 2025 05:34:53 +0000

Bacterial Leaf Blight (BLB) disease caused by Xanthomonas oryzae pv. oryzae (Xoo) continues to be a major threat to rice (Oryza sativa L.) production. The present study was conducted during Kharif seasons 2022-2024 to investigate the virulence of the Raipur Xoo isolate against a set of 28 Near Isogenic Lines (NILs) of IR24 introgressed with various combinations of BLB resistance gene along with local check Bamleshwari, resistant check Improved Sambha Mahsuri, and susceptible check TN-1. The results of artificial inoculation based BLB screening over the three years revealed that most single gene differentials (NILs) lines performed poorly against the Raipur Xoo isolate, where the most frequent resistance reactions ranged from susceptible to highly susceptible indicating the high virulence of the Raipur Xoo isolate. However, among the single gene NILs, the recessive gene xa5 showed relatively stable performance with moderate resistance across the three years. In contrast, NILs possessing two or more resistance genes exhibited improved and more stable resistance, particularly combinations involving xa5, xa13, Xa21, and Xa4. Notably, genotypes such as IRBB-60, IRBB-66, and IRBB-64 consistently displayed moderate to high resistance, emphasizing the advantage of gene pyramiding in conferring durable resistance. Interestingly, the susceptible reaction of the Improved Sambha Mahsuri having three major BLB resistance gene xa5+xa13+Xa21 during Kharif 2024 was against the resistance reaction during Kharif 2022 which further indicated the evolution of the pathogen towards virulence. This highlights the inherent dynamic nature of Xoo and its ability to overcome the existing BLB resistance genes. These findings substantiate the need for continuous monitoring of the pathogen virulence and search for new sources of BLB resistance gene.

Keywords: BLB; Marker Assisted Selection; Resistance breakdown; Artificial inoculation

**Study on gene action and heterotic manifestation of important growth and yield related traits in tomato (Solanum lycopersicum L.) under Terai condition of West Bengal**

Fri, 04 Jul 2025 05:35:08 +0000

A field experiment was conducted in the Department of Vegetable and Spice Crops, Uttar Banga Krishi Viswavidyalaya, Cooch Behar, West Bengal, during the autumn-winter season of 2023-24 to study the nature and magnitude of gene action in the manifestation of important traits and identify promising cross combinations. Seven parental lines and their 10 F_1sproduced by Line × Tester mating were evaluated for 14 traits. Analysis of variance revealed the existence of significant intra-germplasm diversity among lines, testers, and their combinations, as well as the manifestation of significant desired hybrid vigour among the cross combinations due to heterotic effects. Predictability ratio revealed preponderance of non-additive gene action in inheritance of most of the traits and were governed by over-dominance phenomena. Based on GCA estimate B Mut-3 and BCT 115 dg among the lines and Berika among the testers, were observed to be the best combiners with better yield potential. Based on per se performance, combining ability and heterosis the crosses B Mut-3 x Berika, AC Aft x Berika and BCT-115 dg x Berika were observed to be desirable

Keywords: Combining ability, heterosis, tomato, gene action

**Comparative mutagenesis and effect of EMS, Gamma rays and Electron beam on biological parameters of Kalbhat and Black rice (Oryza sativa L.) non-basmati aromatic rice landraces**

Fri, 04 Jul 2025 05:35:17 +0000

Kalbhat and Black rice are two non-basmati scented rice landraces famous for their taste, aroma, and nutritional properties. Mutation was attempted by using ethyl methanesulfonate, gamma radiation, and electron beam in Kalbhat and Black rice. In M₁generation studies, the effect of mutagens on several biological variables was studied, like lethality, chromosomal abnormalities, pollen sterility, and plant survival. In M₂ generation studies, different chlorophyll mutants like Albina, Xantha, Chlorina, and Viridis were identified. The frequency of chlorophyll mutants was relatively higher in Black rice (9.54) as compared to Kalbhat (7.72). Mutagenic effectiveness and efficiency with respect to seedlings height, lethality, and pollen sterility were studied, and the maximum effectiveness and efficiency were observed in EMS treatment in both Black rice and Kalbhat.The lethality and pollen sterility was maximum in EMS treated Kalbhat, while mutagenic efficiency in terms of seedlings height and pollen sterility were maximum in the electron beam treated black rice. EMS was found to be more effective and efficient than gamma radiation and electron beam treatment in both the landraces.

Keywords: Black rice, Effectiveness, Kalbhat, landraces, Mutation frequency.

**Studies on combining ability and gene action for grain yield, head rice recovery and other agronomic traits in rice (Oryza sativa L.)**

Muppani Maneesha, V. Gouri Shankar, B. Srinivas and Y. Hari — Fri, 04 Jul 2025 00:00:00 +0000

For many Asian nations, rice (Oryza sativa L.) is staple food and major source of nutrition. To fulfil the demands of an expanding population the rice production must increase. High temperatures of about 38-42° C and low relative humidity (<40%) is recorded in Telangana in the months of April and May during which the rabi rice crop is at grain filling to maturity stage. These conditions result in low head rice recovery percentage of rabi rice produce. Selection is an important technique in plant breeding and breeders use this method for improving the architecture of a crop by management of available genetic variability (Kohnaki et al., 2013). Breeding strategies based on selection of hybrids require expected level of heterosis as well as specific combining ability. Combining ability analysis is one of the useful tools available to estimate the combining ability effects and aids in selecting the desirable parents and crosses for the exploitation of heterosis.Additionally, it helps in understanding the nature and extent of gene action in the inheritance of specific traits. The Line × Tester analysis method, proposed by Kempthorne in 1957, is the most commonly used approach for identifying general and specific combiners and to study the nature of gene action governing the inheritance of different characters. Therefore, the present research work was carried out to estimate the nature of gene action and combining ability effects of parents and crosses for grain yield and quality traits in rice based on their mean performance, genetic parameters and heterosis.

Keywords:Combining ability,grain yield, head rice recovery, line×tester

**Inquisition on principal component and K- mean clustering analysis for yield and its contributing traits of bread wheat (Triticum aestivum L.)**

Fri, 04 Jul 2025 00:00:00 +0000

An experiment was conducted to assess genetic diversity via K cluster and principal component analysis (PCA) for yield and its contributing characters in 41 bread wheat genotypes at Crop Research Farm, Nawabganj, Chandra Shekhar Azad University of Agriculture & Technology, and Kanpur (U.P.) during Rabi season 2020-21. K- Clustering statistics was used to analyse the genetic divergence in the present group of material. All the 41 genotypes were classified into seven clusters. Cluster I comprised of ten genotypes, cluster II comprised of eight genotypes, cluster III of ten genotypes, clusters IV, V and VI consisted of two genotypes while cluster of VII had seven genotypes. Cluster-VII ranked first in days to maturity, productive tiller per plant, ear length and 1000 seed weight (gm). The maximum contribution towards the expressions of genetic divergence was exhibited by grain yield per plant (30.73%) followed by plant height (31.59%), chlorophyll content (13.41), number of spikelets per spike (6.95%), 1000 grains weight (5.73%), days to 50% flowering (4.63%), ear length (4.36%), days to maturity(1.83%) and number of grains per spike (0.61). Cluster I and VI are most desirable for breeding programme for creating the desired variability and the genotypes in these clusters deserve due consideration for improvement of traits like chlorophyll content, plant height and spike length. The outcomes of this study can contribute to the strategic development of wheat breeding initiatives aimed at exploiting heterosis.

Keywords: Wheat, PCA, genetic diversity, cluster analysis, grain yield.

**Genetic divergence studies for yield and yield components in landraces of rice (Oryza sativa L.)**

Hazimunnisa Mohammad, T. Haritha, B. Krishna Veni and S. Khayum Ahammed — Fri, 04 Jul 2025 05:46:09 +0000

The present investigation was carried out with 36 rice landraces along with four checks to estimate genetic divergence for yield and yield component. Principal component analysis showed that first four principal components viz., PC1, PC2, PC3 and PC4 with eigen value more than one and contributed 86.74% of cumulative variance. Hierarchical cluster analysis by ward’s minimum variance method grouped 40 genotypes including checks into six clusters. Of all the six clusters, cluster III was the largest comprising 14 genotypes followed by cluster I with 11 genotypes, cluster II with seven genotypes, cluster IV with four genotypes, cluster V with three genotypes and cluster VI with one genotype i.e., monogenotypic cluster. The 2D and 3D plots from principal component analysis and clustering pattern from hierarchical cluster analysis indicated that genotypes namely Arakuloya, Narayanakami, Kujipataliya, Tandasagar and Chintaluri sannalu were most divergence for most of the yield and yield components. Molecular diversity analysis using 15 SSR markers revealed that six markers viz., RM154, RM404, RM402, RM85 and RM21 showed polymorphism. Among these, the markers namely RM404 and RM21 recorded higher PIC values. These markers can be considered as more informative and capable of discriminating the genotypes more effectively.

Keywords: Genetic divergence, PCA, Hierarchical cluster analysis, Molecular diversity

**Trait association and genetic diversity analysis in field pea (Pisum sativum var. arvense L.) under timely and late sown conditions**

Fri, 04 Jul 2025 05:46:21 +0000

One hundred and forty three genotypes of field pea including three check varieties were evaluated for morpho-physiological characters under timely and late sown conditions for the study of trait association and genetic diversity. Correlation analysis revealed that for timely and late sown conditions, seed yield per plant showed a strong positive correlation with effective pods per plant, biological yield per plant and plant height. In addition to the above traits, 100-seed weight and pollen viability also exhibited a significant and positive interrelationship with seed yield in late sown conditions. This relationship suggests that selection of more effective pods per plant, biological yield, plant height, 100-seed weight and pollen viability are desirable under late sown conditions to enhance the yield. These traits were also commonly correlated with each other in both environmental conditions. Path coefficient analysis revealed that in timely sown environment, effective pods per plant and biological yield per plant; and in late sown environment, effective pods per plant, biological yield per plant, 100-seed weight, plant height and pollen viability contributed to seed yield directly as well as indirectly. Consequently, it is essential to prioritize these traits when designing a selection strategy for developing high-yielding field pea cultivars. The D² cluster analysis grouped 143 genotypes into 05 multi-genotypic clusters in both sowing conditions. Genotype distribution was different in different environments, suggesting that the environment has an influence on genotype performance.

Keywords: Field Pea, Correlation, Path coefficient, Cluster, Genetic diversity.

**Morphological characterization of strong culm traits and their association with yield performance in rice (Oryza sativa L.)**

Fri, 04 Jul 2025 05:46:36 +0000

Lodging resistance is an important characteristic for enhancing the productivity and stability of rice (Oryza sativa). This study assessed the genetic variability of 81 rice germplasm lines from southern India, focusing on 12 traits contributing for culm structure and yield. A field experiment was conducted in a randomized block design, and the recorded phenotypic data were analysed employing descriptive statistics, variability estimates, correlation analysis, and Principal Component Analysis. The findings revealed high genotypic coefficient of variation and phenotypic coefficient of variation, along with high heritability and genetic advance for culm length of fourth internode, section modulus of fourth internode, and single plant yield. These results indicate strong genetic control and the potential for effective selection for culm traits. Additionally, SPY showed strong positive correlations with the number of productive tillers and hundred seed weight. Plant height, culm length, and culm thickness also exhibited strong correlations with section modulus of fourth internode, highlighting their importance in lodging resistance. The PCA identified three major components that explained 56.16% of the total variability, with culm related traits and yield traits being key contributors. These findings highlight the significance of culm morphology traits in breeding programs and provide valuable insights for parental line selection to enhance rice productivity and develop non-lodging cultivars.

Keywords: rice, culm strength, genetic variability, correlation, PCA

**Induced mutagenesis on growth, yield and yield attributing traits in buckwheat (Fagopyrum tartaricum)**

Vaidurya Pratap Sahi, Nilay Raj, Prashant Kumar Rai and Kiran Kumari — Fri, 04 Jul 2025 05:46:44 +0000

The present study was conducted to assess the impact of induced mutagenesis on the growth, yield, and seedling traits of buckwheat (Fagopyrum tartaricum) using the genotype IC59921, at SHUATS, Prayagraj. The research utilized a Randomized Block Design (RBD) for field trials and a Completely Randomized Design (CRD) for laboratory experiments, incorporating eleven treatments, including a control (T0), ethyl methanesulfonate (EMS) treatments (T1-T4) at concentrations of 0.3% and 0.5% for 3 and 6 hours, as well as gamma irradiation (T5-T10) with doses ranging from 5 to 30 kR. The results showed that EMS treatment at 0.5% for 6 hours significantly enhanced seedling growth and key yield parameters. Additionally, lower doses of gamma radiation positively impacted these traits, while higher doses resulted in reduced germination and overall growth. The study underscores the potential of mutagenesis to improve the growth and productivity of buckwheat, offering a valuable approach for its genetic enhancement in crop improvement programs.

Keywords: Buckwheat, Mutagenesis, EMS, Gamma irradiation.

Genetic diversity studies for morphological characters and micronutrient content in red rice germplasm

Fri, 04 Jul 2025 05:46:59 +0000

Rice is the most staple crop of the world consumed by poorest to richest person in this world. However, rice is a poor source of essential micronutrients such as Iron (Fe) and Zinc (Zn). In rice, evaluating genetic diversity is an essential step during the process of development of trait-specific varieties. Genetic diversity studies among red rice germplasm lines was conducted to evaluate 66 red rice lines for morphological traits and zinc, iron and protein content. Three lines, namely Kalavathi, Misebhatta and Karikagga exhibited unique characters for most of the morphological traits. Correlation studies revealed significant positive association of grain yield with grain zinc content. Cluster analysis classified the 66 red rice germplasm lines into nine distinct clusters. Cluster I was the largest and Cluster VI had germplasm with high zinc content and grain yield per plant. Iron content was highest in cluster VIII. The first five components in the principal component analysis with Eigen values >1 contributed to 66.97% of the total variability. Among the germplasm, Shahara, Hallaga and Karthika recorded high zinc, iron and protein content respectively and could serve as potential source for grain nutritional content in red rice.

Keywords: Red rice, micronutrient content, genetic diversity, cluster analysis